etymology
noun
[ ˌɛtɪˈmɒlədʒi ]
• the study of the origin of words and the way in which their meanings have changed throughout history.
• "the decline of etymology as a linguistic discipline"
Origin:
late Middle English: from Old French ethimologie, via Latin from Greek etumologia, from etumologos ‘student of etymology’, from etumon, neuter singular of etumos ‘true’.